Lhc As A Photon-Photon Collider: Bounds On Gamma(X ->Gamma Gamma)

In the relatively recent CMS data, there is a hint on the existence of a resonance with the mass 28 GeV decaying to a mu(+)mu(-) pair and produced in association with a b quark jet and a second jet. Such a resonance should also couple to photons through the fermion loop, therefore, it can be searched for in ultraperipheral collisions (UPC) of protons. We set an upper bound on the X-gamma gamma coupling constant from the data on mu(+)mu(-) pair production in UPC at the LHC. Our approach can be used for similar resonances should they appear in the future.